Positional accuracy and measurement error in digital databases of land use: an empirical study

This paper discusses the issues of positional accuracy and measurement error in the context of a large empirical study of landscape change in England and Wales. The epsilon band model of digitizing accuracy is used to make estimates of the levels of positional uncertainty and measurement error that is due to digitizing polygon outlines. The degree of error expected had the same polygons been captured in raster format is then determined. These results prompt a general discussion of the nature of error in spatial databases.     

Establishing a framework for Open Geographic Information science

When conducting research within a framework of Geographic Information Science (GISc), the scientific validity of this work can be argued as highly dependent upon the extent to which the methods employed are reproducible, and that, in the strictest sense, can only be fully achieved by implementing transparent workflows that utilize both open source software and openly available data. After considering the scientific implications of non-reproducible methods, we provide a review of both open source Geographic Information Systems (GIS) and openly available data, before describing an integrated model for Open GISc. We conclude with a critical review of this embryonic paradigm, with directions for future development in supporting spatial data infrastructure.     

Application of GIS Processing Techniques for Producing Mineral Prospectivity Maps—A Case Study: Mesothermal Au in the Swayze Greenstone Belt,Ontario, Canada

A Geographic Information System (GIS) is used to prepare and process digital geoscience data in a variety of ways for producing gold prospectivity maps of the Swayze greenstone belt, Ontario, Canada. Data used to produce these maps include geologic, geochemical, geophysical, and remotely sensed (Landsat). A number of modeling methods are used and are grouped into data-driven (weights of evidence, logistic regression) and knowledge-driven (index and Boolean overlay) methods. The weights of evidence (WofE) technique compares the spatial association of known gold prospects with various indicators (evidence maps) of gold mineralization, to derive a set of weights used to produce the final gold prospectivity map. Logistic regression derives statistical information from evidence maps over each known gold prospect and the coefficients derived from regression analysis are used to weight each evidence map. The gold prospectivity map produced from the index overlay process uses a weighting scheme that is derived from input by the geologist, whereas the Boolean method uses equally weighted binary evidence maps.The resultant gold prospectivity maps are somewhat different in this study as the data comprising the evidence maps were processed purposely differently for each modeling method. Several areas of high gold potential, some of which are coincident with known gold prospects, are evident on the gold prospectivity maps produced using all modeling methods. The majority of these occur in mafic rocks within high strain zones, which is typical of many Archean greenstone belts.     

Building Environmental Literacy through Participation in GIS and Multimedia Assisted Field Research

Abstract

A Learning Support System (LSS) that emphasizes experiential research in natural environments using the cutting-edge technologies of GIS and multimedia has been developed for teaching environmental literacy to undergraduate students at the University of Georgia. Computers are used as cognitive tools to create a context in which students become interns in an ecological research center. Students are instructed to conduct research in the form of two field laboratories (the stream and forest laboratories). They accomplish their tasks by collecting data in the field (the State Botanical Garden of Georgia near the campus). They enter the data in the Learning Support System (LSS), and are guided to formulate hypotheses relating to stream water quality and human impact on forest succession for testing. Students also interact with the Environmental Research Support Site (ERSS) within the LSS for explanations to their findings. A specially customized Arc View GIS program within the LSS provides a tool to students for spatial analysis in the case of the forest laboratory. Students and faculty evaluations as well as final examination results confirmed the receptiveness of students to the LSS approach and its effectiveness in the learning of environmental literacy.     

Investigating the Spatiotemporal Links Between Disorder,Crime, and the Fear of Crime

While links between social and physical disorder, crime, and the fear of crime have long been areas of research interest, few studies have looked at these links from a spatiotemporal viewpoint. This is somewhat surprising, as many of the factors associated with disorder, crime, and fear are known to vary over time and space. This paper uses GISystems to investigate potential spatiotemporal links between these areas in Wollongong, New South Wales, with specific focus on links between graffiti and the fear of crime. The results reveal that the distribution of fear of crime varies considerably over time and is often spatially coincident with concentrations of disorder. Graffiti was found to be one of the most prevalent types of physical disorder. The results are discussed in the context of the “broken windows” thesis and strategic intervention at the community level.     

Reflections and speculations on the progress in Geographic Information Systems (GIS): a geographic perspective

Great strides have been made in Geographic Information Systems (GIS) research over the past half-century. However, this progress has created both opportunities and challenges. From a geographic perspective, certain challenges remain, including the modelling of geographic-featured environments with GIS data model, the enhancement of GIS’s analysis functions for comprehensive geographic analysis and achieving human-oriented geographic information presentation. Several basic theoretical and technical ideas that follow the workflow and processes of geographic information induction, geographic scenario modelling, geographic process analysis and geographic environment representation are proposed to fill the gaps between GIS and geography. We also call for designing methods for big geographic data-oriented analysis, making best use of videos and developing virtual geographic scenario-based GIS for further evolution.     

青海旅游资源信息系统设计

应用系统以ArcInfo和ArcView为开发平台 ,以软件工程理论为指导依据 ,应用GIS技术、数据库技术和模块设计技术为基本的技术支持 ,设计了青海旅游信息系统的结构及数据库 ,使用Avenue语言进行二次开发 ,并利用VisualBasic和Flash进行了界面开发及模块实现。该系统可实现青海旅游信息专题图浏览 ,景点查询、定位 ,多媒体方式介绍 ,以及路线选择功能 ,能为游客提供图、文、声并貌的旅游向导 ,实现了青海旅游资源的计算机化宣传 ,也可为GIS技术在青海盐湖资源、水力资源信息技术的应用提供借鉴     

Students’ Perceptions of Their Engagement Using GIS-Story Maps

This article describes the findings of a qualitative phenomenographic study that explored students’ engagement from the perspective of the students. It describes how the participants perceived their engagement when they learned social studies using GIS Story Maps. Qualitative data collection involved classroom observations, student-written reflections, and oral interviews with fourteen eighth-grade student-participants. The data analysis revealed that students perceive Story Maps as engaging in four qualitatively different ways: generating inquiry, visualizing information, mapping interactively, and cycling. Students also see a geographic and cultural connection between Story Maps and their lives, and additional connections beyond the classroom.     

Medium and short-term channel planform changes on the Rivers Tay and Tummel, Scotland

Channel planform change was analysed using a variety of data-sources for the medium-term (>25 years and <250 years) and short-term (<25 years) on a reach of the Rivers Tay and Tummel, Scotland. Map data were input into a Geographic Information System (GIS) and used to determine planform characteristics and changes in width, braiding index and sinuosity for the study reach between 1755 and 1976. Aerial photographs were utilised to determine the more recent changes that had taken place between 1971 and 1994. The analysis showed that significant changes had occurred over the medium term with a mean reduction in channel width of 34% for this period. These changes are comparable to those found in studies of similar European rivers for this period. Changes determined for the short-term displayed a continuance of this trend at a comparable rate of change. An analysis of flood frequency and magnitude, precipitation and discharge records for both periods does not show an associated decrease and therefore does not reflect the changes in channel planform. Evidence points towards flood embankment construction in the mid-1800s as the initial cause of channel change for the study reach which was later exacerbated by flow regulation. Incision and the subsequent stabilisation of lateral and mid-channel gravel bars by vegetation succession has resulted in an overall increase in the stability of the study reach which has persisted even where the embankments have fallen into disrepair.     

The Implementation and Effectiveness of Geographic Information Systems Technology and Methods in Secondary Education

Abstract

Geographic information systems (GIS) technology and methods have transformed decision-making in society by bringing geographic analysis to the desktop computer. Although some educators consider GIS to be a promising means for implementing reform, it has been adopted by less than 2 percent of American high schools. The reasons behind the interest in GIS, its slow implementation, and its effectiveness in teaching and learning are unclear. To address these concerns, this research describes the extent to which GIS is being implemented in American secondary education and assesses the effectiveness of lessons that use GIS. A survey of 1,520 high schools that own GIS software, along with experiments and case studies in three high schools, provided primary data for assessing the implementation and effectiveness of GIS.     

Localized income inequality, concentrated disadvantage and homicide

Several theories (e.g., routine activities, strain and social disorganization theories) suggest that there are effects of income inequality and concentrated disadvantage on crime. This study follows primarily the long line of social disorganization theorizing to explain the intraurban variation of homicide rates in Chicago. In addition to poverty, income inequality adds stress to individuals when they compare their situation to those around them. A localized income inequality (LII) index is implemented in a Geographic Information System (GIS) to measure the inequality between contiguous areas. Defining inequality in a localized context is important because geographic proximity permits close contacts between residents and thus reinforces the awareness of relative deprivation. This inequality index adds a new dimension to concentrated disadvantage in urban areas. The study shows that the new concentrated disadvantage measure is a strong predictor of homicide rates across three areal units of analysis in Chicago, i.e., census tracts, community areas and neighborhood clusters.     

Spatio-temporal analysis of flowering using LiDAR topography

Spatio-temporal patterns of flowering in forest ecosystems are hard to quantify and monitor. The objectives of this study were to investigate spatio-temporal patterns(e.g. soilssimple slope classesslope aspectand flow accumulation) of flowering around Lake IssaqueenaSouth Carolina(SCUSA) using plant-flowering database collected with GPS- enabled camera(stored in Picasa 3 web albums and project website) on a monthly basis in 2012 and Li DAR-based topography. Pacolet fine sandy loam had the most flowering plantsfollowed by Madison sandy loamboth dominant soil types around the lake. Most flowering plants were on moderately steep(17%–30%) and gently sloping(4%–8%) slopes. Most flowering plants were on west(247.5°–292.5°)southwest(202.5°–247.5°)and northwest(292.5°–337.5°) aspects. Most flowering plants were associated with minimum and maximum flows within the landscape. Chi-square tests indicated differences in the distributions of the proportions of flowering plants were significant by soil typeslopeaspectand flow accumulation for each month(February-November)for all months(overall)and across months. The Chi-square test on area-normalized data indicated significant differences for all months and individual differences by each month with some months not statistically significant. Cluster analysis on flowering counts for nine plant families with the most flowering counts indicated no unique separation by clusterbut implied that the majority of these families were flowering on strongly sloping(9%–16%) slopeson southwest(202.5°–247.5°) aspectsand low flow accumulation(0–200). Presented methodology can serve as a template for future efforts to quantify spatio-temporal patterns of flowering and other phenological events.     

Prediction of Aquifer Vulnerability to Pesticides Using Fuzzy Rule-Based Models at the Regional Scale

Contamination of ground water has been a major environmental concern in recent years. The potential for ground-water contamination by pesticides depends on porous media, solute, and hydrologic parameters. Although sophisticated deterministic computer models are available for assessing aquifer-contamination potential on a site-by-site basis, most deterministic models are too complex for vulnerability assessment on a regional scale because they require input data that are spatially and temporally variable, and which may not be available at this scale. Therefore, development of an affordable model that is robust under conditions of uncertainty at the watershed scale with minimum input of field data becomes a useful ground-water management tool. The purpose of this study was to examine the usefulness of fuzzy rule-based techniques in predicting aquifer vulnerability to pesticides at the regional scale. The objectives were to (1) develop fuzzy rule-based models using the same input parameters contained in an index-based model (i.e., the modified DRASTIC model), (2) determine the sensitivity of fuzzy rule model predictions, (3) compare the outputs of the fuzzy rule-based models with those of the modified DRASTIC model and with the results of aquifer water-quality analyses, and (4) examine the spatial variability of field parameters around contaminated wells of the Alluvial aquifer in Woodruff County Arkansas. The fuzzy rule-based model for objective (1) was developed using similar parameter weights and ratings as the modified DRASTIC model. For objective (2), fuzzy rule-based models were created using fewer parameters than the modified DRASTIC model. Sensitivity of the fuzzy rule-based models was determined using different combinations of weights of the four input parameters in DRASTIC. It was found that variations in the weights of the input parameters and number of fuzzy sets influenced the location of the aquifer-vulnerability categories as well as the area within each fuzzy category. The fuzzy rule models tended to predict somewhat higher vulnerabilities of the Alluvial aquifer than the modified DRASTIC model. The fuzzy rule base that had the soil-leaching index (S) as the highest weight was chosen as the best fuzzy rule model in predicting potential contamination by pesticides of the aquifer. In general, the fuzzy rule models tended to overestimate the vulnerability of the aquifer in the study area.     

Replication of a terrain stability mapping using an Artificial Neural Network

Subjective geomorphic mapping is a method commonly used for landslide hazard zonation. This method relies heavily on the skills and experience of the mapper, and therefore, its major drawbacks are the high costs and lack of consistency between products generated by different terrain mappers. In this study a method for cost-effective and consistent replication of subjective geomorphic mappings is demonstrated, by using a type of Artificial Neural Network named Learning Vector Quantization. This paper presents a study conducted in the Canadian province of British Columbia employing a high-quality data set. By utilizing Learning Vector Quantization, stable and unstable terrains were delineated with a similarity of approximately 91%, compared to the mapping produced by terrain specialists. Also, in this process, slope, elevation, aspect, and existing geomorphic processes were identified as the terrain attributes that contributed most to the quality of the mapping.     

Book Reviews

Books reviewed:
Roderick P. Neumann, Imposing Wilderness: Struggles over Livelihood and Nature Preservation in Africa
Richard A. Schroeder, Shady Practices: Agroforestry and Gender Politics in The Gambia
Adebayo Adedeji (ed.), Comprehending and Mastering African Conflicts: The Search for Sustainable Peaceand Good Governance
Hilgard O'Reilly Sternberg, A água e o homem na várzea do Careiro     

Book Reviews

Books reviewed: Arne, Kalland and Gerard, Persoon (eds) Environmental Movements in Asia M., Kellman and R., Tackaberry Tropical Environments: The Functioning and Management of Tropical Ecosystems Gavin, Daws and Marty, Fujita Archipelago: The Islands of Indonesia From the Nineteenth‐Century Discoveries of Alfred Russel Wallace to the Fate of Forests and Reefs in the Twenty‐First Century Nihal, Perera Decolonizing Ceylon: Colonialism, Nationalism and the Politics of Space in Sri Lanka     

Book Reviews

Books reviewed:
Maruja M.B. Asis, (ed.) The Philippines as Home: Settlers and Sojourners in the Country.
Hans Gooszen, A Demographic History of the Indonesian Archipelago, 1880–1942.
Karin Bras, Image-Building and Guiding on Lombok: The Social Construction of a Tourist Destination.
K.S. Chon, (ed.) Tourism in Southeast Asia: A New Direction.     

Book Reviews

Cresswell, TimIn Place/Out of Place: Geography, Ideology, and Transgression Cho, GeorgeTrade, Aid and Global Interdependence Colten, Craig E. and Skinner, Peter N.The Road to Love Canal: Managing Industrial Waste before EPA DeMers, Michael N.Fundamentals of Geographic Information Systems Frantz, Klaus and Sauder, Robert A. (eds)Ethnic Persistence and Change in Europe and America: Traces in Landscape and Society Hardwick, Susan Wiley and Holtgrieve, Donald G.Valley for Dreams: Life and Landscape in the Sacramento Valley Herbert, StevePolicing Space: Territoriality and the Los Angeles Police Department Jackson, TimMaterial Concerns: Pollution, Profit and Quality of Life King, Russell; Connell, John, and White, Paul (eds)Writing across Worlds: Literature and Migration Majumdar, S. K.; Miller, E. W., and Brenner, F. J. (eds)Environmental Contaminants, Ecosystems and Human Health Tuathail, Gearóid ÓCritical Geopolitics: The Politics of Writing Global Space Pinch, StevenWorlds of Welfare: Understanding the Changing Geographies of Social Welfare Provision Poulsen, Thomas M.Nations and States: A Geographic Background to World Affairs Reid, DavidSustainable Development: An Introductory Guide Simmie, James (ed.)Innovation, Networks and Learning Regions?     

Book Reviews

Basso, Keith H. Wisdom Sits in Places: Language and Landscape among the Western Apache Foote, Kenneth E. Shadowed Ground: America's Landscapes of Violence and Tragedy Harries, Keith and Cheatwood, Derral The Geography of Execution: The Capital Punishment Quagmire in America Larkham, Peter J. Conservation and the City James, Preston E. and Martin, Geoffrey J. All Possible Worlds: A History of Geographical Ideas Meir, Avinoam As Nomadism Ends: The Israeli Bedouin of the Negev Ruddick, Susan M. Young and Homeless in Hollywood: Mapping Social Identities Smith, Neil The New Urban Frontier: Gentrification and the Revanchist City